JP2005272760A - ε-type crystal copper phthalocyanine and process for producing the same - Google Patents

Abstract

[PROBLEMS] To improve a method for producing an ε-type crystal copper phthalocyanine which requires a large amount of energy and has a large equipment load and environmental load.
Copper phthalocyanine, which is an α-type crystal alone or a mixture with an ε-type crystal obtained by an acid pasting method or an acid slurry method, is mixed in a solvent in the presence of a Lewis acid such as iodine, bromine and quinones in an amount of 80 to 250. Ε-type crystalline copper phthalocyanine is produced by treating at ℃.
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Description

TECHNICAL FIELD The present invention relates to an ε-type crystal copper phthalocyanine having a single exothermic peak in a temperature range of 425 ± 25 ° C. by differential thermal analysis at a heating rate of 5 ° C. · min ⁻¹ in an air atmosphere and a method for producing the same. It is.

ε-type crystal copper phthalocyanine has a red hue, high vividness, and high tinting strength compared to α-type crystals, and the solvent resistance to crystal growth of primary crystals is larger than β-type crystals. Crystalline molecular aggregates with extremely excellent characteristics that there is less concern of hue change and coloring power and sharpness reduction due to higher solvent resistance to crystal transition of other homogeneous heterogeneous copper phthalocyanines It is. Furthermore, the thermodynamic stability of the ε-type crystal is next to the β-type, which is the most stable crystal form among homogenous heterocrystalline crystals.

A typical method for producing ε-type crystal copper phthalocyanine is a solvent salt milling method in which copper phthalocyanine having a crystal form other than ε-type and β-type is milled in an organic solvent for a long time by applying a strong mechanical force (Patent Document). 1).
The biggest factor that makes it difficult to control the transition to the ε-type crystal form is thought to be its molecular arrangement similar to the β-type. Peaks with diffraction angles of 7.5 ° and 9.0 ° characteristic of CuKα powder X-ray diffraction profile of ε-type crystals are attributed to reflection on Miller index 001 and 20 planes, respectively, and molecules similar to β-type The structure was estimated by crystal structure analysis. It is considered that the strong mechanical force in the conventional manufacturing method plays a role of not passing through the molecular arrangement of the β-type crystal form having the minimum potential energy and suppresses the transition to the β-type.
JP-A-48-76925

The problems to be solved are that the production of ε-type crystalline copper phthalocyanine requires a strong mechanical force that greatly reflects the cost from the viewpoint of energy and time, as well as the salts used as grinding aids, High boiling solvents with a high COD value must be used, which is a heavy load on equipment and the environment.

The present invention relates to an ε-type crystalline copper phthalocyanine having a single exothermic peak in a temperature range of 425 ± 25 ° C. according to differential thermal analysis at a heating rate of 5 ° C. · min ⁻¹ in an air atmosphere.

    Furthermore, this invention relates to the manufacturing method of the said (epsilon) type crystal form copper phthalocyanine obtained by processing copper phthalocyanine in a solvent at 80-250 degreeC by coexistence of a Lewis acid.

    Furthermore, the present invention relates to the above production method wherein the Lewis acid is iodine.

    Furthermore, the present invention relates to the above production method, wherein the Lewis acid is bromine.

    Furthermore, this invention relates to the said manufacturing method whose Lewis acid is quinones.

Furthermore, the present invention relates to the above production method, wherein the copper phthalocyanine is an α-type crystal alone or a mixture with an ε-type crystal.

Furthermore, the present invention relates to the above production method, wherein the copper phthalocyanine is an α-type crystal alone or a mixture with an ε-type crystal obtained by an acid pasting method or an acid slurry method.

Copper phthalocyanine is the most important indigo pigment among organic pigments in terms of hue, resistance and cost. Among them, the ε-type crystal form copper phthalocyanine is a molecular assembly having extremely excellent aptitude for use. As a result of the realization without the strong mechanical force as in the prior art, the load on energy and equipment and the environment can be drastically reduced and the production can be carried out extremely advantageously industrially.

The copper phthalocyanine in the present invention can be obtained by adding copper phthalocyanine to 5 to 15 times by weight 65 to 100% sulfuric acid and stirring for 3 to 8 hours to give a sulfate or sulfuric acid solution and injecting it into 30 to 50 times by weight water, or Copper phthalocyanine is added to 65 to 100% sulfuric acid in an amount of 5 to 15 times by weight and stirred for 3 to 8 hours to obtain a sulfate or sulfuric acid solution, which is injected into 30 to 50 times by weight of water to obtain fine α-type crystal form copper phthalocyanine. As described above, sulfuric acid is generally used as an acid. When sulfuric acid having a concentration of 80% or more is used, copper phthalocyanine is called an acid pasting method because it is in a highly viscous solution state. When 80 to 80% sulfuric acid is used, copper phthalocyanine is called the acid slurry method because its sulfate is dispersed.

The crystal form of copper phthalocyanine in the present invention is not limited to the α-type crystal form, but may be a crystal form having a larger potential energy than the ε-type crystal form, for example, a δ or γ-type crystal form. Is advantageous.

The solvent in the present invention is a tertiary alkylbenzene such as tert-butylbenzene or tert-amylbenzene, an alicyclic group such as nitrobenzene or sulfolane, or a mixture thereof.
The processing temperature in this invention is 80-250 degreeC, Preferably it is 120-180 degreeC. If the temperature is lower than 80 ° C., the α type does not transition to the ε type. When the temperature is higher than 250 ° C., primary crystals grow, which is disadvantageous as a pigment and wastes heat energy.

The Lewis acid in the present invention is iodine, bromine, benzoquinone, naphthoquinone, p-chloranil quinones, and iodine and bromine are particularly excellent. The ligand field of the central metal copper atom of the copper phthalocyanine molecule in β-type is an octahedral structure composed of 4 pyrrole nitrogen atoms in the molecule and 2 meso-position nitrogen atoms in the adjacent copper phthalocyanine molecule. This structure is a factor of β-type stability. The action of the mechanical force referred to in the background section mechanically suppresses the axial coordination of two meso-position nitrogen atoms in the adjacent copper phthalocyanine molecule to the copper atom and prevents the transition to the β-type crystal form. It is thought that. In contrast, Lewis acids are chemically suppressed. The meso-position nitrogen atom has the highest frontier electron density in the copper phthalocyanine molecule, and therefore has high coordination ability for acid and metal vacancies. The Lewis acid is thought to reduce the electron density of the meso-position nitrogen atom by forming a charge transfer complex with copper phthalocyanine and suppress the coordination to the copper atom. The usage-amount in this invention is 0.01-2.0 molar ratio with respect to the phthalocyanine compound whole quantity, Preferably, it is 0.05-0.5.

In the solvent treatment, it is preferable that ε-type crystal copper phthalocyanine coexists as a seed crystal. This is because the seed crystal has the effect of increasing the initial transition rate by the crystal nucleus action. The amount used is suitably 1/5 to 1/10 based on the total amount of the mixture of copper phthalocyanine and phthalocyanine derivative.

Specific surface area / m ² · g ⁻¹ of the ε-type crystal copper phthalocyanine obtained by the present invention by BET method is a large value of 60 ± 5, and it is a pigment as it is in gravure ink, offset ink, paint, or colored resin. It was quality that can be used as. Ε-type crystalline copper phthalocyanine in the form of solvent-treated slurry, purified solvent slurry or powder obtained by the present invention, and pigment by solvent milling method or solvent salt milling method with or without phthalocyanine derivative As a result, coloring power and sharpness could be further improved, and extremely high-quality pigments could be easily produced.

Further, the gravure ink is obtained by treating the ε-type crystalline copper phthalocyanine in the form of a solvent-treated slurry, purified solvent slurry or powder obtained by the present invention with a surfactant, or by dry blending or slurry blending a phthalocyanine derivative. When used in offset inks, paints, colored resins, etc., application suitability could be given.

The ε-type crystalline copper phthalocyanine obtained by the present invention does not contain a phthalocyanine derivative, and has a single exothermic peak in a temperature range of 425 ± 25 ° C. according to differential thermal analysis at a heating rate of 5 ° C./min ⁻¹ in an air atmosphere. It was one. This analysis result shows that no phthalocyanine compound other than copper phthalocyanine is contained, and was realized for the first time by the production method of the present invention.

(Comparative example)
Add 73 parts by weight of crude copper phthalocyanine and 7 parts by weight of tetrachlorophthalimidomethylated copper phthalocyanine (the number of substitution of tetrachlorophthalimidomethyl group is 1 / mol) to 500 parts by weight of 95% sulfuric acid and stir for 3 hours to obtain a sulfuric acid solution. Injection into 4 L of water. After filtration, the residue was washed with water and dried with hot air, and the α-type crystalline copper phthalocyanine obtained was pulverized. Next, the obtained mixture of copper phthalocyanine and phthalocyanine derivative was put in a kneader together with 20 parts by weight of ε-type crystalline copper phthalocyanine, 600 parts by weight of pulverized sodium chloride, and 100 parts by weight of polyethylene glycol, and the mixture was polished at 100 to 140 ° C. for 10 hours. Crushed. After removal, the mixture was purified with a 2% sulfuric acid solution, filtered, washed with water, and dried. The obtained pigment was in the ε-type crystal form. The powder X-ray diffraction profile is shown in FIG. In addition, FIG. 2 shows a DTA curve obtained by differential thermal analysis at a temperature rising rate of 5 ° C. · min ⁻¹ in an air atmosphere.

85 parts by weight of crude copper phthalocyanine was added to 500 parts by weight of 98% sulfuric acid and stirred for 3 hours to obtain a sulfuric acid solution, which was poured into 4 L of water through an aspirator. After filtration, the residue was washed with water and dried with hot air, and the α-type crystalline copper phthalocyanine obtained was pulverized. Next, the obtained fine α-type crystal copper phthalocyanine was heated and stirred at 170 ° C. for 6 hours in 1000 parts by weight of sulfolane together with 15 parts by weight of ε-type crystal copper phthalocyanine and 4 parts by weight of iodine. After cooling to near room temperature, it was poured into 1000 parts by weight of methanol, filtered, and the residue was washed with methanol and dried with hot air. Ε-type crystalline copper phthalocyanine containing no α-type or β-type was quantitatively obtained by powder X-ray diffraction analysis. The powder X-ray diffraction profile is shown in FIG. Further, FIG. 4 shows a DTA curve obtained by a differential thermal analysis method at a heating rate of 5 ° C. · min ⁻¹ in an air atmosphere. While the exothermic peak in the temperature range of 425 ± 25 ° C. is two in the comparative example, Example 1 is single, and the difference due to the presence or absence of the derivative is clear.

80 parts by weight of crude copper phthalocyanine was added to 500 parts by weight of 98% sulfuric acid and stirred for 3 hours to form a sulfuric acid solution, which was poured into 4 L of water through an aspirator. After filtration, the residue was washed with water and dried with hot air, and the α-type crystalline copper phthalocyanine obtained was pulverized. Next, the obtained fine α-type crystal copper phthalocyanine was stirred with heating at 130 ° C. for 10 hours in 1000 parts by weight of sulfolane together with 20 parts by weight of ε-type crystal copper phthalocyanine and 8 parts by weight of bromine. After cooling to near room temperature, methanol 1
After pouring into 000 parts by weight and filtering, the residue was washed with methanol and dried in hot air. Ε-type crystal copper phthalocyanine containing no α-type or β-type was quantitatively obtained by powder X-ray diffraction analysis.

Powder X-ray diffraction profile of ε-type crystalline copper phthalocyanine obtained in Comparative Example DTA curve of ε-type crystalline copper phthalocyanine obtained in Comparative Example Powder X-ray diffraction profile of ε-type crystalline copper phthalocyanine obtained in Example 1 DTA curve of ε-type crystal copper phthalocyanine obtained in Example 1

Claims (7)

Ε-type crystal form copper phthalocyanine having a single exothermic peak in a temperature range of 425 ± 25 ° C. by differential thermal analysis at a heating rate of 5 ° C./min ⁻¹ in an air atmosphere. The method for producing ε-type crystalline copper phthalocyanine according to claim 1, obtained by treating copper phthalocyanine in a solvent at 80 to 250 ° C in the presence of a Lewis acid. The process according to claim 2, wherein the Lewis acid is iodine. The process according to claim 2, wherein the Lewis acid is bromine.
The process according to claim 2, wherein the Lewis acid is a quinone. The process according to claim 2, wherein the copper phthalocyanine is an α-type crystal alone or a mixture with an ε-type crystal. 3. The production method according to claim 2, wherein the copper phthalocyanine is an α-type crystal obtained by an acid pasting method or an acid slurry method, or a mixture with an ε-type crystal.